The World Wide Web is increasingly becoming a more important and more frequently used form of communication between people. The primary form of web-based communication is electronic mail. Other forms of communication are also used, however, such as news groups, discussion groups, bulletin boards, voice-over IP, and so on. Because of the vast amount of information that is available on the web, it can be difficult for a person to locate information that may be of interest. For example, a person who receives hundreds of electronic mail messages a day may find it impractical to take the time to store the messages in folders of the appropriate topic. As a result, it may be difficult for the person to later find and retrieve all messages related to the same topic. A similar situation arises when a person tries to locate news groups or discussion groups of interest. Because there may be no effective indexing of these groups, it can be difficult for the person to find groups related to the topic of interest.
Some attempts have been made to help the retrieval of information of interest by creating web directories that provide a hierarchical organization of web-based information. The process of creating the directories and deciding into which directory a particular piece of information (e.g., a news group) should go is typically not automated. Without an automated approach it is impractical to handle the massive amounts of web-based information that are being generated on a daily basis. Moreover, because a person may not be fully aware of the entire web directory hierarchy or may not fully understand the semantics of information, the person may place the information in a directory that is not the most appropriate, making later retrieval difficult. It would be desirable to have an automated technique that would help organize such information.